Best player for iPhone, pad

The music player in yr iPhone/iPad plays lossless AIFF, WAV and Apple Lossless. No need to purchase a new player.

There's FLACplayer that I use to play FLAC but it is not as easy to manage my playlists and library with that.

ps there's a hardware limitation on iOS devices that limits playback to 48kHz and 44.1kHz. So no 88.2, 96 or 192kHz material will be played natively

Yes but as some articles have stated, that's a hack that works and we don't know if Apple would disable this. As we know, the same connector doesn't allow that same feature on the iPhone so we know it can be locked out.

The official Apple endorsed method (eg using a Cypher Solo DAC type device or a digital dock like the Wadia) is still limited to 44/48kHz IIRC

USB Camera Kit is an attachment to the iPad and adds a USB Type A port and makes the iPad a USB host.

Using a regular A to B cable, you can connect that USB port to a USB DAC. This works as long as the DAC is USB Audio Class 1.0 compliant (up to 24/96)

I use XLD on Mac to rip my CDs to AIFF. XLD can also rip to WAV and Apple Lossless (runs a compressed lossless algorithm like FLAC).

XLD works similarly to EAC which does error correction and checks against an online database.